• Current Industrial and Technological Trends in Aerospace
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• v.8 no.1
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• pp.77-85
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• 2010

The current GPS constellation consists of 32 Block IIA/IIR/IIR-M satellites including 12 Block IIA satellites on service over 15 years. The satellites in poor space conditions may suffer from anomalies, especially influenced by aging atomic clocks which are of importance positioning and timing. Recently, the IGS Ultra-rapid predicted products have not shown acceptably high quality prediction performance because the Block IIA cesium clocks may be easily affected by various factors such as temperature and environment. The anomalies of aging clocks involve lower performance of positioning in the GPS applications. We, thus, describe satellite clock behaviors and anomalies induced by aging clocks and their detection technologies to avoid such anomalies.

• Journal of Distribution Research
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• v.4 no.3
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• pp.47-64
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• 2000

This study introduces the mother logit model to predict consumer's store choices. The model is not based on the IIA assumptions and thus accounts for substitution among similar alternatives. The choice data as an input to the model is obtained through the conjoint-type choice experiment. The model is applied to consumer's choice of fastfood stores in the context where new store enters the market. The analysis shows that the substitution effects are significant and therefore the mother logit model predicts better than the IIA model. The mother logit model will be useful as well for the market structure analysis in capturing cannibalization among several brands.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.709-716
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• 1998

Three kinds of anti-complementary system and macrophage activating polysaccharides, AB-20-Ia, AB-20-IIa-2a and AB-20-IVa-2 were isolated from the fruit body of Agaricus bisporus and their structures were characterized. The proteoglycan, AB-20-IVa-2 showing the most potent anti-complementary and macrophage activity was composed of glucose, galactose, mannose, xylose, fucose and arabinose in a molar ratio of 3.48:1.83:1.00:0.79:0.74:0.11 and its main component amino acids were phenylalanine (34.72%) and valine (27.84%). The neutral polysaccharides, AB-20-Ia and AB-20-IIa-2a showing lower activity than AB-20-IVa-2, consisted of xylose, glucose, mannose, fucose and arabinose in molar ratios of <0.05:<0.05:2.07:1.00:2.72 and 2.16:1.58:1.00:0.20:0.14, respectively. The molecular weights of AB-20-Ia, AB-20-IIa-2a and AB-20-IVa-2 were 840,000, 750,000 and 650,000 respectively. In the $^1H-\;and\;^{13}C-NMR$ spectra of AB-20-Ia and AB-20-IIa-2a, AB-20-Ia showed only ${\beta}-configuration\;(^1H:\;4.8\;ppm,\;^{13}C:\;107.0\;ppm)$ in the anomerization of the glycosidic linkages, while AB-20-IIa-2a had both ${\alpha}-anomer\;(^1H:\;5.4\;ppm,\;^{13}C:\;102.0\;ppm)\;and\;{\beta}-anomer$. Especially, AB-20-Ia and AB-20-IIa-2a showed acetyl signals $(^1H:\;2.5\;ppm,\;^{13}C:\;21.0\;ppm)$. In the methylation analysis of the three polysaccharides, high proportion of 1,6-linked glucofuranosyl residues were detected in AB-20-Ia, whereas 1,6-linked glucopyranosyl residues and branches linked at position 4 of those mainly contained in AB-20-IIa-2a. AB-20-IVa-2 consisted mainly of 1,2-linked xylofuranosyl residues and 1,6-linked glucopyranosyl residues and branches linked at position 3 of those.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.5
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• pp.335-345
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• 2022

Pyroptosis is an inflammatory form of programmed cell death that is linked with invading intracellular pathogens. Cardiac pyroptosis has a significant role in coronary microembolization (CME), thus causing myocardial injury. Tanshinone IIA (Tan IIA) has powerful cardioprotective effects. Hence, this study aimed to identify the effect of Tan IIA on CME and its underlying mechanism. Forty Sprague-Dawley (SD) rats were randomly grouped into sham, CME, CME + low-dose Tan IIA, and CME + high-dose Tan IIA groups. Except for the sham group, polyethylene microspheres (42 ㎛) were injected to establish the CME model. The Tan-L and Tan-H groups received intraperitoneal Tan IIA for 7 days before CME. After CME, cardiac function, myocardial histopathology, and serum myocardial injury markers were assessed. The expression of pyroptosis-associated molecules and TLR4/MyD88/NF-κB/NLRP3 cascade was evaluated by qRT-PCR, Western blotting, ELISA, and IHC. Relative to the sham group, CME group's cardiac functions were significantly reduced, with a high level of serum myocardial injury markers, and microinfarct area. Also, the levels of caspase-1 p20, GSDMD-N, IL-18, IL-1β, TLR4, MyD88, p-NF-κB p65, NLRP3, and ASC expression were increased. Relative to the CME group, the Tan-H and Tan-L groups had considerably improved cardiac functions, with a considerably low level of serum myocardial injury markers and microinfarct area. Tan IIA can reduce the levels of pyroptosis-associated mRNA and protein, which may be caused by inhibiting TLR4/MyD88/NF-κB/NLRP3 cascade. In conclusion, Tanshinone IIA can suppress cardiomyocyte pyroptosis probably through modulating the TLR4/MyD88/NF-κB/NLRP3 cascade, lowering cardiac dysfunction, and myocardial damage.

• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.332-339
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• 1995

Water-soluble polysaccharide (FCW) was extracted from the fruiting body of Fomitella fraxinea with neutral sodium chloride solution. The polysaccharide was further fractionated into FCW-I and FCW-II by ion exchange chromatography. The FCW-I and FCW-II were then purified by gel permeation chromatography and named as FCW-Ia and FCW-IIa, respectively. FCW-IIa showed relatively strong immuno-stimulating activity but FCW-Ia did not. By analyses of HPLC and GPC, FCW-Ia and FCW-IIa were identified to be homogeneous and their molecular weights were estimated to be about 15,000 and 8,700, respectively. FCW-Ia consisted of fucose, galactose, and mannose as main sugars and their molar ratio was 19.5 : 63.2 : 25.0. Protein was not detected in FCW-Ia. However, FCW-IIa was composed of glucose, galactose, and mannose at a molar ratio of 1.0 : 0.3 : 0.4 and contained 0.4% protein with a higher amount of glutamic acid. A small amount of uronic acid was detected in both FCW-Ia and FCW-IIa.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.4
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• pp.106-114
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• 2012

As Incheon International Airport(IIA) is located in an island 50-km away from Seoul, various travel equipments for access are required. So far two connecting bridges are constructed funded by civilian funds. For the further bridge construction, the reduction of forecast traffic amount and the government subsidy for the civilian funds are big issues. Comparing the access traffics of IIA to those other competing airports, traffic conditions inside the airport are superior to other competing airports from the management point of view, as utilization conditions and equipment capacities are periodically monitored and evaluated to set up comprehensive countermeasures following constructing by stages. However, while the accessability to IIA is very important, as IIA is built on an island the conflicts between near-by developers and traffic facility operators make further bridge construction difficult. As improving the accessibility to an airport is not easy to achieve only by the IIA management's efforts, the central government level authorities should organize a committee with agencies concerned and analyze the characteristics of access traffic periodically to suggest reform measures for each organization concerned to implement appropriate undertakings at apt timing. For the future, central government's level empirical research on the airport accessibility for synthetic and systematic plan set-up is expected.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.236-239
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• 2011

This paper introduces the design concepts and characteristics of WinDS3000$^{TM}$(TC IIa) which is a trade name of Doosan's 3MW offshore/onshore wind turbine. WinDS3000$^{TM}$(TC IIa) has been designed in consideration of high Reliability, Availability, Maintainability and Serviceability (RAMS) and low cost of electricity (CDE) for the TC IIa condition based on GL guideline. An integrated drive-train design with an innovative three-stage gearbox has been introduced to minimize nacelle weight of the wind turbine and to enhance a high reliability for transmission. A permanent magnet generator with full converter system has been introduced to get higher efficiency in partial load operation and grid-friendly system for both 50 Hz and 60 Hz. A pitch-regulated variable speed control system has been introduced to control wind turbine power while generator reaction torque can be adjusted almost instantaneously by the associated power electronics. The wind turbine has been also equipped with condition monitoring and diagnostic systems in order to meet maintainability requirements.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.3C
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• pp.315-326
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• 2003

Abstract In this paper, an improved index assignment procedure is proposed to reduce the channel error effect in a communication system employing classified vector quantization(CVQ). The proposed algorithm consists of two parts: inner index assignment (IIA) and cross index assignment (CIA). The II A reduces the distortion resulting from the error in order bits, presenting the identity of each code vector in a subcodebook. The CIA modifies the indexes assigned by the IIA in such a way that the effect of the channel error occurring in class bits, indicating the class information of the code vector, can be minimized. Simulation results show that the proposed algorithms enable a reliable communication over noisy channels even without employing the channel encoding. Index Terms Classified vector quantization, index assignment.

• Journal of the Korea Safety Management & Science
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• v.25 no.1
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• pp.51-58
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• 2023

Determination of explosion reference pressure is important in designing and testing flameproof enclosures (Ex d). Although relative humidity affects to explosion pressure, its effect is not well investigated for the gas group IIB, IIA, and I. This study tested explosion pressure for Ethylene (8 vol.%), Propane (4.6 vol.%), and Methane (9.8 vol.%), which are the representative gas of the gas group IIB, IIA, and I, at ambient temperature and atmospheric pressure (1 atm) under different relative humidity (0% ~ 80%). Ethylene- and Propane-air mixed gases generally tended to decrease as the relative humidity increased; however, explosion pressure was largely dropped at 20% of relative humidity compared to 0% and 10% of relative humidity. On the other hand, Methane-air mixture gas showed similar pressures at 0% and 10% of relative humidity; but no explosion occurred at more than 20%. The results of this study can be used in setting a testing protocol of explosion reference pressure for designing and testing a flameproof enclosure.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4301-4305
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• 2014

Tanshinone IIA is a pharmacologically active ingredient extracted from Danshen, a Chinese traditional medicine. Its molecular mechanisms are still unclear. The present study utilized computational approaches to uncover the potential targets of this compound. In this research, PharmMapper server was used as the inverse docking tool andnd the results were verified by Autodock vina in PyRx 0.8, and by DRAR-CPI, a server for drug repositioning via the chemical-protein interactome. Results showed that the retinoic acid receptor alpha ($RAR{\alpha}$), a target protein in acute promyelocytic leukemia (APL), was in the top rank, with a pharmacophore model matching well the molecular features of Tanshinone IIA. Moreover, molecular docking and drug repurposing results showed that the complex was also matched in terms of structure and chemical-protein interactions. These results indicated that $RAR{\alpha}$ may be a potential target of Tanshinone IIA for APL. The study can provide useful information for further biological and biochemical research on natural compounds.